That is a lot in little time.

18- Brings you up to 2008. At least 6 months basic training, then if you are immediately enrolled in sniper training that is 24 months. You need to fit officer training on after that which can be another... twelve I believe. SO that is 42 months of training which is 3 years and a bit which brings you up to 21. You then have 3 years to make 18 HVT kills as I doubt it is possible within a course of 3 months. Depending on high up, do you mean like minor warlords or major warlords? As a lot of them are hard to find. Hell 18 kills in a short amount of time like that is impressive for snipers now adays.

I'll see if Echo has any other issues for you to address.